Field of the Invention
The present invention relates to HIV-1 envelope protein gp140 and HIV-1 envelope trimers, as well as an HIV vaccine.
Related Art
The trimeric envelope glycoprotein spike of HIV-1 mediates virus entry into human cells. The exposed part of the trimer, gp140, consists of two noncovalently associated subunits, gp120 and gp41 ectodomain. The surface of an HIV-1 virus is covered with 20-50 trimeric envelope spikes that are embedded in the viral envelope. The spike makes the first contact with the human T cell during sexual transmission of the virus. This interaction triggers a series of events leading to fusion of viral and host membranes and delivery of the virus nucleocapsid core into the host cell. This results in the establishment of HIV infection in the human host. A vaccine containing recombinantly produced viral trimers that mimics native spike might elicit trimer-specific antibodies, which by binding to the virus can disable envelope protein (Env) function and block the transmission of HIV into humans. Therefore, development of a recombinant trimer immunogen as a vaccine has been one of the top priorities in the hunt for an effective HIV vaccine. However, preparation of authentic HIV-1 trimers has been challenging. The procedures developed so far have not produced authentic trimers, which appear as three-blade propeller shaped particles when visualized by an electron microscope.